Redwood Creek Conclusion
The Redwood Creek assessment team considered a great deal of information regarding basin processes related to stream conditions in the basin. The large body of existing scientific studies and reports that portray physical and biological watershed characteristics were combined with the multidisciplinary investigations and integrated synthesis performed by the NCWAP team. This large data base provided a substantial amount information for analysis, interpretation and for addressing the NCWAP assessment questions and making recommendations to improve stream habitat conditions.
The Redwood Creek Basin sustains populations of Chinook and coho salmon, steelhead and sea run coastal cutthroat trout. Present populations of these anadromous salmonids are overall less abundant and less widely distributed compared to their historic presence in the basin. Impairments to freshwater and estuarine habitat have been identified as leading factors in the decline of salmonid populations. The conservation of Redwood Creek’s anadromous salmonids largely relies on improving existing habitat conditions through a reduction in sediment delivery to streams, instream improvement projects, and promoting conifer growth in near stream forests. Increasing coho salmon and summer steelhead populations presents the greatest challenges due to their low abundance in the basin and specific habitat requirements. The poor habitat conditions of the estuary/lagoon will likely impede juvenile Chinook survival before ocean entry until major actions are taken to restore historic ecosystem processes in the Redwood Creek estuary/lagoon.
There are good stream habitat conditions found in each of the subbasins. Streams located in the undisturbed portion of the Prairie Creek Subbasin provide some of the best salmonid habitat in the basin. However, sites in the Prairie Creek Subbasin (managed by RNSP since 1968) that endured impacts from past land use still exhibit impaired conditions related to excessive sediments and disturbed forests. These findings illustrate that relatively short term disturbance to watersheds can have long term effects to stream systems and salmonid populations. Similar impacts to habitat and fishery resources are found throughout the basin.
Timber harvest is the dominant land use in the Redwood Creek basin and is of significant socio-economic importance both for employment to local residents and as a source of building materials. Stream condition improvements and increasing anadromous salmonid populations largely depends on achieving a balance between the socio-economic needs for timber resources and implementing management needed to maintain or improve basin conditions that sustain viable fish populations. Recently enacted timber harvest rules include watercourse protections zones and sediment-potential-reducing improvements to roads and other regulatory measures intended to help sustain or improve basin integrity. Effective timberland and other land use management and watershed improvement projects such as road and instream habitat treatments are steps needed to improve aquatic habitat conditions and help increase numbers and distribution of salmonids.
General trends in the watershed are toward the improvement of a number of the factors that currently are limiting salmonids. Recovery appears to be occurring in terms of declining amounts of stored sediment in many stream channels and increasing tree growth in riparian areas. If stream habitats continue to move towards pre 1964 disturbance conditions, anadromous salmonid populations should respond by increasing in numbers and distribution across the basin.
The Redwood Creek basin is an excellent candidate for a successful long-term, programmatic watershed improvement effort. The likelihood that The Redwood Creek basin will react in a responsive manner to management improvements and restoration efforts is largely a function of existing basin conditions and future land use considerations. A good knowledge base of current watershed conditions and processes is essential for developing watershed improvement activities and monitoring effectiveness of such projects. Acquiring this knowledge requires property access. Access is a requirement to design, implement, monitor, and evaluate suitable improvement projects. Thus, systematic improvement project development is dependent upon the cooperative attitude of resource agencies, watershed groups and individuals, and landowners and managers. Reaching that goal is dependent upon the formation of a well organized and thoughtful improvement program founded on broad based community support for the effort.